Neumann KH 310a and/vs PMC TB2s - various, including positioning

[Dan B]

In a bout of upgraditis, I’m toying with adding some Neuman KH310a’s to my setup.

I currently have PMC TB2+ with the passive XB1 sub, powered by Flying Mole DAD-M100 amps. (I also have some Rega Kytes as secondary speakers for checking translation on systems with little low end, but very rarely use them.) I gather the 310s ought to be quite a step up (else I won't bother!).

So, a few questions:

1. Are the 310s likely to render the PMCs totally redundant? Seems it might be useful to hold on to them because: (a) I’ve had TB2s in my life for over a decade, and have them in my kitchen hi-fi and living room (TV/hifi) setups, so am well familiar; and/or (b) low end extension available with the XB1 sub (down to about 25hz – albeit that’s probably overkill for a room of my size – see pic – although it is extensively acoustically treated). Oh, and I’m notoriously bad at decluttering (need to Marie Condo my life!). But I guess there are upsides of losing the TB2s and the sub: their second hand value; creating space (the sub is huge); being able to keep the Regas (or I could have Dynaudio BM5s in their place); and not having the acoustic interference of the mounting options (see 2).

2. Space is limited, so if I keep both, positioning is likely to be tricky. See embedded pics below. What’s the best approach?

a. Mount the PMCs horizontally (rather than vertically - on their existing stands (tweeters outermost) and sit the 310s horizontally (as they are intended to be) on top. That should just about fit. This will put the PMC tweeters below ear level, which is sub optimal but their dispersion pattern is reasonably wide and they’d only be there as secondary speakers, I suspect seeing little use. I don’t know whether/how much horizontal mounting of this PMC two-way speaker is an issue. I’m guessing in this scenario it might be useful to put blue tac (or mouse mats or MoPads or something else?) between 310s and the PMCs (and between the PMCs and the stands, as I do currently).

b. Leave PMCs where they are and replace Regas with 310s, mounted horizontally. To get them to fit (they’re much bigger than the Rega’s – basically the same size as the PMCs but a 5cm wider), I’d need to bring the stands forward to create space for them and toe them in a fair bit. . They’d be quite widely spaced, but with rockwool to their immediate sides, so the sweet spot would be further back. That’s not really too much of a problem as I have a 42” screen and can sit further back, and the 310s are kinda between near- and mid-fields. Albeit you hear more room in the mix the further back you are…

c. Third option would be to mount the 310s vertically on the stands the PMCs are currently on (I’ve not seen the 310s mounted vertically… is that an issue?). And I might just be able to squeeze the PMCs mounted horizontally onto the stands the Regas are on (again, bringing the stands forward a little).

Wide angle lens view (apologies for the mess!) http://tinypic.com/r/2d8ggsj/9

Close (right) http://tinypic.com/r/29p6h00/9

Close (left - showing stands) http://tinypic.com/r/mmardv/9

Normal full view http://tinypic.com/r/9gk7s5/9

3. Is there anything else I should be giving serious consideration too / anything in the up to £3k bracket worth considering instead? The 310s appeal as their active, 3 way and sealed, so quite different to the TB2s, and seem to have amazing reviews.

FYI, the PMCs are currently mounted as per the diagram below – supposedly technically the “correct” place for this room (2’11” from side walls, 3’3” from the rear wall, measure to the front edge of the cabinets; optimal listening position is purportedly 6’11” from the half wall in front. (Ignore the couch - there is no couch!)

/ http://tinypic.com/r/ws0f8z/9

The room dimensions:

/ http://tinypic.com/r/5w00gw/9

Many thanks in advance!

Dan

[Dan B]

P.S. I've not so far managed to get the images to embed properly using IMG in square brackets as usual, so have linked them. Any tips on that front welcome!

Room height is 1.97m

[Wonks]

I can see the images just fine. Sometimes they can be slow to load.

[John Willett]

I think Hugh Robjohns would be the best to answer this as he has (or has had) both PMC and the KH310 himself.

[Hugh Robjohns]

It's largely pointless running both the KH310 and TB2 in the same system. The KH310 is substantially more revealing and accurate and so the TB2 on its own will serve no useful purpose. But you could use them to extend your other music systems for surround sound! (And see below)

The KH310s will need higher stands than the TB2s to get the midpoint between tweeter and midrange dome at ear level, and don't mount them vertically, whatever you do. They're not designed to be used that way and the performance will suffer significantly. (The same applies to running the TB2s sideways, actually -- or the Regas for that matter -- it messes up the stereo imaging and midrange clarity.)

Having said all that, the TB2/XB1 combo will give significantly more low end power than the KH310s on their own, and that might be relevant if you're into EDM or something. Personally, I find the KH310 low end adequate for most things, and I use decent headphones to check anyway because of the inevitable room anomalies...

You could experiment with the XB1 in partnership with the KH10s if you want, To fill out the very bottom octave, but I suspect you'll need to introduce bespoke filtering to get a good match through the crossover region, and there may well be a noticeable change of character.

H

[Dan B]

Glad the images have worked!

Thanks all. Hugh's comments (as always!) are most helpful.

Reassuring to hear that the 310s really are in a different league.

I'd suspected/feared that the TB2s and Kytes shouldn't be used on their sides (and similarly, the 310s not vertically). I could swap the stands around, which ought to resolve the height issues (having the 310s on the inside on the higher stands, and the PMCs or Regas (or perhaps nothing...!) on the outer, lower ones.

I should disclose that I use this space for studio work, as well as an office space, so it gets used for general listening. It may be that the TB2/XB1 combo is more fun/forgiving for that... ?. So there might be sense in retaining them here (and using the Regas as rear speakers in the surround setup! ).

I occasionally work on (and more frequently listen to) EDM, so it's nice to have access to that lowest octave, even if only for (somewhat inaccurate, given the room - despite vast amounts of trapping) listening enjoyment.

Since the XB1 is passive, it (currently) runs by taking the speaker level outputs from the Flying Moles, with the TB2s as satellites directly off of the XB1 (again, at speaker level). Were I to delete the TB2s/Regas, to use the XB1 with the 310s, I'd have to run the XB1 by itself (i.e. Flying Moles into the XB1, but not using the crossover into the 310s). Upside of that is I could use the FMs to adjust the sub volume. Downside is the (lack of) crossover ... Not sure whether/how that could be resolved... Some kind of variable custom crossover...? Sounds expensive..

Perhaps a cheaper and more viable alternative would be to keep the TB2s or Regas, and run them with the FMs/XB1. I suspect the Regas (fast, tight, fun, musical and bright, but no low end to speak of) and XB1 combo might actually be quite fun! (Plus I think it's going to be a tight squeeze to have 310s and TB2s). Though I can well imagine that with the 310s, why would you ever listen to anything else...

[Jack Ruston]

I’m going to make a, possibly incorrect, assumption.

From the images I’m going to suggest that the acoustics of this positioning are not ideal. Far from ideal actually. You’re wedged up into a corner with lots of flat reflective surfaces very nearby....ceiling, desk, a massive display. You’ve got two sets of speakers in close proximity to each other, which typically disturbs the imaging, and forces at least one, if not both, to be in the wrong place. As an experiment, remove the display, and the B monitors, and place a big sofa cushion on the desk surface. Do things change?

Into this confusion you have a sub. Subs are essential for 5.1 and above, but they’re tricky in small domestic spaces and usually do more harm than good.

My instinct would be to simplify this setup as much as possible. Use one set of speakers in the right place, with no sub. Modify the environment as much as possible. These days, your B set should be something with bass enhancement, like a Sonos, over in the corner behind you somewhere.

Whether the main monitors should be 310’s or something else is something only you can decide. I’d want something as room independent as possible in that space.

[Dan B]

Hi Jack,

Yes, I'm sure you're right re acoustics. Whilst the rest of the room is heavily treated (vast amouts of trapping and early reflection points treated), the screens, desk and B monitors (the Kytes) surely don't help. For critical work, I have a 4" deep rockwool "plug" that squeezed into the angled Velux window; I could also put another Rockwool panel/acoustic foam/large cushion over the screen(s) and/or desk. But for general day to day, I need the screens and desk; and I'm afraid I'm stuck with the positioning of the whole setup in the room.

The B speakers are set back a good few inches from the PMCs, so hopefully that doesn't affect the PMCs, just the Kytes. I'm not too bothered by the Kytes being compromised (their horizontal positioning, as Hugh says, also won't be doing them any favours) since it's really just for very occasionally listening to a mix on different speakers (with no real low end to speak of).

One thing I haven't installed yet (though have) is a cloud above the mixing chair. I spoke to an acoustician, who said it wasn't needed because (I suspect in part because of the angling of the ceiling) that reflections from the ceiling wouldn't be reaching the listening position.

For all that, it does sound pretty sweet with the PMCs (and I have a custom box which enables me to switch off the sub) in the space (at least, given the constraints of the room - the dimensions being essentially c.3x5x2m (so 1 x 1:5 x 2:5 ratio - far from ideal). I should really get round to measuring it now that it's treated...

I can see the logic to just having the 310s, correctly positioned without flanking speakers causing interference. And maybe playing with the sub, powered separately via the FMs (set to a very low level), to see if that adds anything (though I suspect it may just confuse things and/or I might just use it for low end listening pleasure rather than for studio work - to be fair, it sees more use as an office hifi at the moment (day job, a baby and a toddler not being particularly conducive to spare time in the studio!).

[Dan B]

Well, somewhat in haste...

In Hugh we trust!

So I've been demoing some KH310s in my room today. Hastily setup (was too impatient and don't have the right cables to hand without dismantling other things, so they're running on very long unbalanced leads and positioning may be a little sub-optimal, but they're at least slightly forward of the PMCs). But even thrown up hastily like this...



...they are indeed in a different league. I've not A/B'd properly with the PMCs yet, but bass extension is impressive (better if I recall correctly than the TB2s on their own; not as low as with the XB1p - but for most purposes I don't generally feel like I'm missing out on anything). Imaging, clarity, resolution, detail - all quite a step up! Mid-range much clearer and cleaner. I'm hearing things I'd not before. And smiling even more (the PMC TB2+/XB1p Flying Mole combo was pretty darned good on that front).

Despite the quite substantial damage to the wallet, I think these'll be keepers. Really looking forward to mixing on them; revisiting old mixes has already been quite insightful!

I should be able to A/B properly next week (a friend is popping round with his Presonus V2 Monitor Station and maybe a pair of Mitchell and Todd monitors - 301a's I think - which we can throw into the mix).

I suspect (/hope) the outcome will be that there's little sense in keeping the TB2s (even as hifis speakers for general listening; though I may hold onto the sub). That would mean I could move the 310s a bit closer together so the mid drivers are approximately where the tweeters of the PMCs are. According to advice I had from an acoustician, that (where the PMCs are) is the best spot for the room, given the lay out and the room (see diagram in my first post; I'm not sure why, but hey). So that may improve things further. The 310s might be a slightly too far apart at the moment, but it doesn't seem to be much of an issue.

A few questions:

1. If I keep both PMCs and Neumanns, is there anything particularly wrong with the current positioning/anything I can do to improve things? Or the proposed positioning if the TB2s go?

2. The 310s are on heavy, sand filled stands, 1m high. I'm proposing to put a triangle of blu-tac blobs to fix the speakers to the stands. I have MoPads but can't see much logic in using them on top of stands. I'm not sure there's much/anything to gain by doing anything else - though feel free to enlighten me!

3. This puts the tweeters at ear height (or slightly below if I don't slouch, but mostly I do!). Ceiling is 1.98m and the manual says to avoid having them at 0.8 - 1m. from a ceiling ("Avoid a distance “dwall” of 0.8 to 1 m (2' 6" to 3') from a solid wall behind the loudspeaker. Similarly, avoid these distances from solid side walls or a solid ceiling. Respecting these positioning limitations reduces the chances of dips and peaks in the low frequency response (comb filtering) caused by strong reflections.)

So on 1m stands, with a c.2m ceiling, they're pretty much exactly 0.8 - 1m from the ceiling. I don't think/hope that's not an issue here (not least as there's not really much of a way round that) because the speakers are under the sloped part of the wall at this point - it's nearly another meter before the ceiling reaches full height, so the speakers themselves aren't 0.8-1m from the ceiling at the point their positioned (much closer, in fact).

4. Any other tips welcome.

Am thinking I might get a Drawmer CMC2 or MC2.1 to go with it (I'm currently using a hifi preamp - Cambridge Audio C500 with unbalanced connections).

Thanks all!

Dan

[Dan B]

I should probably add that there's a LOT of rockwool in this room - about 18 or so 2' x 4' panels (a mix of 4" and 6"), plus a couple of large tri-corner chunks of rockwool (behind the desk). There's even more stuffed into the walls behind the double-plasterboard/Green Glue - albeit for isolation purposes. I gather glass is pretty transparent when it comes to bass frequencies, so with the window and glass bi-folds, and the oodles of trapping, it seems to sound pretty good (though I really should measure it to see what's going on...)

[Jack Ruston]

They look like they're too wide - too far apart.

I'd strongly consider the MC2.1. It's amazing.

J

[Dan B]

Thanks.

I took the plunge on a CMC2. Great bit of kit and means I can run everything with balanced cables. Couldn't really justify spending double on the MC2.1, tempting though it was.

Ideally yes, the Neumans would be a bit closer in. The best listening position (equalateral triangle) requires me to sit back a bit - but that's fine.

That said, I'm struggling to find a justification to hold onto the PMC setup (Hugh - right again, as always!). To the extent I keep a B speaker setup, I think a grotbox/Avantone cube (maybe even just one)/even the Rega Kytes (since they've no real low end to speak of) would be more valuable. So I'm thinking I'll move the Neumanns in, delete the PMC setup and maybe use some cheap hifi speakers like the Kytes (on the outsides) and/or get a Avantone mix cube (perhaps just one). Debating whether to go for the active one or use an old hifi amp to power the passive (I have a Pioneer A400, and maybe a cheap Cambridge Audio amp I could use).

Thanks all for the advice. The Neumanns really are revealing/clarifying details that'd previously eluded me!

[Wonks]

No point going overboard on a high-spec amp for your grot-boxes. Might as well use a standard hi-fi amp for hi-fi speakers as that's what the majority of people (who still have a hi-fi) will be using.